Inflatable dunnage bags are commonly used for cushioning loads shipped in trucks, trailers and containers transported by ships, trucks or rail. This is often the case when the cargo only partially fills the container and there exists the possibility of shifting during transport that could cause damage. Typically known dunnage bags are constructed of one or more layers of paper or woven polypropylene surrounding a plastic lining. The paper protects the bags from tearing—thus more layers are used in applications where the risk of damage to the dunnage bag is greater. Furthermore, for inflating and deflating the dunnage bag, a valve is attached by way of a hole cut in the bag during manufacture.
The dunnage bags are shipped flat from the manufacturer, and are inflated by packing and loading personnel as the containers are loaded with cargo. The bag is firstly placed in the space that it will occupy as cargo is loaded into a container, secondly the inflation device is attached to a valve of the dunnage bag and subsequently the dunnage bag is filled with air until an appropriate air pressure within the bag is achieved. Typically this occurs within a few seconds.
Various types of inflation devices exist for inflating containers with non-rigid walls and air-filled bags, such as sacks and dunnage bags commonly used to cushion cargo loads. Known inflation devices include tire inflation tools which have been converted or adapted and are attached to a hose leading from a source of compressed air. Some inflation devices incorporate venturi tubes and are often known as venturi air-flow guns, which include a venturi tube, namely an air passage with a region of restricted diameter. In terms of Bernoulli's law (i.e. the inverse relationship between air velocity and pressure), passage of air through the restricted region of a venturi tube creates a low-pressure region resulting in a suction effect used to draw air out of an attached container.
Unfortunately the known type of inflation devices are difficult to operate and not flexible in operation and thus suffer from important limitations. Furthermore in practice it must be ensured that an inflated bag is fully inflated.
It is an object of the invention to suggest an inflation device which will assist in overcoming the aforesaid problems.